Discussion with mini review of the literature:
Furcation involvement is a major factor hindering the prognosis of molar teeth because of the difficulty in maintaining an area free from dental plaque. Root resection and/or amputation is a possible strategy for managing this situation by creating an area that is more accessible for oral hygiene measures. Several previous studies have evaluated the long-term success of this procedure. 1920-25. Table 1 summarizes some of the studies available in the literature with their main findings.
The success rate ranged from 100% 14,26 to 40%27; however, a systematic review published in 2009 reported the survival rate to range between 62%-100% over an observation periods of 15-13 years28. A more recent systematic review published during 2020 indicated an overall survival rate of 38%–94.4% which is similar to that of scaling and root planing and open flap debridement. 29 The difference in success rates between studies can be attributed to several factors, including the criteria for case selection, type of final restoration, follow-up duration, and criteria for defining success.30
Derks et al. evaluated the long-term survival rates of root-resected teeth over approximately 30 years. They reported a cumulative survival rate of 90.6% for the first 10 years, which decreased considerably thereafter, with a median survival duration of 20 years after root resection. 31
Owing to the importance of proper case selection and careful performance of the procedure for improving the overall survival rate, several authors have attempted to define the essential criteria for determining procedural success.
Newel attributed failures to residual root fragments and furcation lips and ledges that were not properly identified and managed during surgery,32 while Carnevale et al. considered osseous recontouring and apical repositioning of the flap essential for procedural success. 33
Mjzoob and Kon stressed the importance of careful evaluation of the procedure and proper planning for subsequent restorations because only 8% of root-resected molars have favorable periodontal support postoperatively. 34
Park reported that teeth with >50% residual supporting bone had higher survival rates. 35 In contrast, Lee et al. reported an increased risk for procedural failure in teeth with mobility ≥ grade 2 before root resection and removal of the supporting bone. 27 Persistent mobility of any degree after phase-one therapy and the involvement of two or more proximal surfaces were considered contraindications by Klavan et al. 23
Rasperini presented a decision tree wherein root amputation/resection was indicated only for cases with grade 3 furcation involvement with the vertical component of the furcation not exceeding the middle third of the root and attachment loss limited to only one root.36
The choice between maintaining a tooth with root amputation or replacing it with a dental implant is debatable. Fugazzotto et al. compared the success rates of root-resected molars to those of dental implants placed in the molar region and found success rates ranging between 95.2%–100% over 15 years of observation, with cumulative success rates of 96.8% for root-resected molars and 97% for implants.37 Zafiropoulos et al. reported a complication rate of 32.1% in root-resected molars compared to 11.1% in implants in the molar region over approximately 4 years. 38 Similarly, Kinsel et al. reported a 15.9% failure rate for root-resected molars compared to 3.6% for single implants. 39
Higher failure rates for implants in the maxillary molar region are attributed to the bone quality in that region. 40Simonis et al. reported complications in approximately 48.03% of implants. 41 Therefore, all factors should be considered and treatment options should be discussed with the restorative dentist and presented to the patient before finalization of the treatment plan.
In this case, root amputation successfully maintained the form and function of the dentition for more than 10 years. We believe that problems only started when the patient showed reduced compliance with maintenance visits. Even though, we think that this treatment gave the patient the chance to postpone bone grafting and dental implant placement for better timing. Placing implants earlier might have led to the development of peri-implantitis owing to the difficulties associated with their maintenance.